CN109921468B - Parallel operation control method for small single-phase generator set - Google Patents
Parallel operation control method for small single-phase generator set Download PDFInfo
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Abstract
The invention relates to the technical field of parallel operation of generator sets, in particular to a parallel operation control method of a small single-phase generator set, which comprises the following steps: acquiring single-phase current input and single-phase voltage input of each small-sized single-phase generator set in a parallel operation state respectively at the same time, and analyzing to obtain corresponding active power data, reactive power data and frequency data; adjusting the exciting current value of the corresponding small single-phase generator set according to the reactive power data; adjusting the output power of the corresponding engine according to the active power and the frequency data; and judging whether to trigger an inverse power protection mechanism of the small single-phase generator set according to the active power data. And analyzing the active power data and the reactive power data to adjust the excitation current value of the corresponding small single-phase generator set and serve as a judgment standard for triggering a protection mechanism of the small single-phase generator set so as to ensure the parallel operation of the small single-phase generator set and furthest improve the effective utilization rate of the generator.
Description
Technical Field
The invention relates to the technical field of parallel operation of generator sets, in particular to a parallel operation control method of a small single-phase generator set.
Background
When the generator supplies power to the load, the situation that the load power is far greater than the power of a single generator, so that the generator power is insufficient and the load cannot be driven may occur. In this case, the usual solution is to combine multiple generators to power the load, known as "generator-parallel operation". In the prior art, the condition of the parallel operation of the generator is strict, and the parallel operation of the generator can be realized only when the output voltage and frequency of each generator are basically equal and the phases are similar in the parallel operation process, and the reactive power balance and the active power balance can be kept in the operation after the parallel operation. When reactive power is unbalanced, excitation, over-excitation and under-excitation occur. One of the units is provided with reverse reactive power, and the other unit is provided with reactive power in the total load and reverse reactive power of the underexcited unit additionally, so that reactive currents of the two units are large, and overload of the unit current is caused when the active power is not large, namely, the load is not carried. When the active power is unbalanced, the output of the two machines is unbalanced, one of the active power bands is more than the rated power, namely the other active power band is not up to the rated power when the active power band is fully loaded, so that the power carried by the two machines after the two machines are combined is smaller than the added power of the two machines. For example, when two 5KW generator sets are combined, one set reaches 5KW, and the other set only reaches 4KW, the two sets add up to 9KW, but do not reach 10KW, and only two sets are combined to achieve the maximum power, so that the power is balanced as much as possible. And when the generator set is operated in parallel, if one of the engines fails, the set still absorbs power from the power grid, and the generator motor drives the engine to run to reverse power, so that the connection of the set and the power grid must be released.
Therefore, a parallel operation control method of the small single-phase generator set is urgently needed, and intelligent control of the generator is achieved, so that parallel operation of the small single-phase generator set is guaranteed.
Disclosure of Invention
The technical problems to be solved by the invention are as follows: the parallel operation control method for the small single-phase generator set is used for realizing intelligent control of the generator so as to ensure the parallel operation of the small single-phase generator set.
In order to solve the technical problems, the invention adopts the following technical scheme:
a parallel operation control method of a small single-phase generator set comprises the following steps:
acquiring single-phase current input and single-phase voltage input of each small-sized single-phase generator set in a parallel operation state respectively at the same time, and analyzing to obtain corresponding active power data, reactive power data and frequency data;
adjusting the exciting current value of the corresponding small single-phase generator set according to the reactive power data; adjusting the corresponding engine output power according to the active power and the frequency data; and judging whether to trigger an inverse power protection mechanism of the small single-phase generator set according to the active power data.
Further, the excitation current value of the corresponding small-sized single-phase generator set is adjusted according to the reactive power data, and specifically:
when the reactive power data is positive, the exciting current value of the corresponding small single-phase generator set is reduced; when the reactive power data is negative, the exciting current value of the corresponding small single-phase generator set is increased.
Further, the corresponding machine output power is adjusted according to the active power and the frequency data, specifically:
and judging whether the difference between the output frequency of each small single-phase generator in full load and the output frequency in no load is out of a preset threshold range, and if so, adjusting the corresponding engine output power according to the active power and the frequency data.
Further, the preset threshold range is 3-7%.
Further, whether a protection mechanism of the small single-phase generator set is triggered is judged according to the active power data, and the protection mechanism is specifically as follows:
and when the active power data is negative and the absolute value of the active power data is greater than 10% of the total power, controlling the corresponding small-sized single-phase generator set to be disconnected and in parallel with other small-sized single-phase generator sets.
Further, the distortion rate of the output waveform of the small single-phase generator set is less than 10%.
Further, the output power of the small single-phase generator set is smaller than 10KW.
The invention has the beneficial effects that:
according to the parallel operation control method of the small single-phase generator sets, a mode of independent control of each small single-phase generator set is adopted, and single-phase current input and single-phase voltage input of each small single-phase generator set in a parallel operation state are respectively and simultaneously obtained, so that corresponding active power data, reactive power data and frequency data are obtained through analysis; the active power data, the reactive power data and the frequency data are further analyzed to adjust the exciting current value and the engine output power of the corresponding small single-phase generator set and serve as judgment standards for triggering the reverse power protection mechanism of the small single-phase generator set, intelligent control of the generator is achieved, parallel operation of the small single-phase generator set is guaranteed, and the effective utilization rate of the generator is improved to the greatest extent.
Drawings
FIG. 1 is a flow chart of the steps of the parallel operation control method of the small single-phase generator set of the invention;
FIG. 2 is a diagram showing the connection of circuits used in the implementation of the parallel operation control method of the small-sized single-phase generator set of the present invention;
FIG. 3 is a partial circuit connection diagram of a measurement and control unit of a circuit used for implementing the parallel operation control method of the small single-phase generator set of the invention;
FIG. 4 is a diagram showing a connection between a fourth chip and a peripheral circuit of a measurement and control unit of a circuit used for implementing the parallel operation control method of the small-sized single-phase generator set of the present invention;
FIG. 5 is a diagram showing a fifth chip and its peripheral circuit connection of a measurement and control unit of a circuit used for implementing the parallel operation control method of the small-sized single-phase generator set of the present invention;
fig. 6 is a circuit connection diagram of a second pin row of the measurement and control unit of the circuit adopted in the implementation of the parallel operation control method of the small single-phase generator set.
Detailed Description
In order to describe the technical contents, the achieved objects and effects of the present invention in detail, the following description will be made with reference to the embodiments in conjunction with the accompanying drawings.
The most critical concept of the invention is as follows: and the active power data, the reactive power data and the frequency data are analyzed by adopting an independent control mode of each small single-phase generator set so as to adjust the excitation current value and the engine output power of the corresponding small single-phase generator set and serve as a judgment standard for triggering the reverse power protection mechanism of the small single-phase generator set, thereby realizing intelligent control.
Referring to fig. 1, the parallel operation control method of a small single-phase generator set provided by the invention comprises the following steps:
acquiring single-phase current input and single-phase voltage input of each small-sized single-phase generator set in a parallel operation state respectively at the same time, and analyzing to obtain corresponding active power data, reactive power data and frequency data;
adjusting the exciting current value of the corresponding small single-phase generator set according to the reactive power data; adjusting the corresponding engine output power according to the active power and the frequency data; and judging whether to trigger an inverse power protection mechanism of the small single-phase generator set according to the active power data.
From the above description, the beneficial effects of the invention are as follows:
according to the parallel operation control method of the small single-phase generator sets, a mode of independent control of each small single-phase generator set is adopted, and single-phase current input and single-phase voltage input of each small single-phase generator set in a parallel operation state are respectively and simultaneously obtained, so that corresponding active power data, reactive power data and frequency data are obtained through analysis; the active power data, the reactive power data and the frequency data are further analyzed to adjust the exciting current value and the engine output power of the corresponding small single-phase generator set and serve as judgment standards for triggering the reverse power protection mechanism of the small single-phase generator set, intelligent control of the generator is achieved, parallel operation of the small single-phase generator set is guaranteed, and the effective utilization rate of the generator is improved to the greatest extent.
Further, the excitation current value of the corresponding small-sized single-phase generator set is adjusted according to the reactive power data, and specifically:
when the reactive power data is positive, the exciting current value of the corresponding small single-phase generator set is reduced; when the reactive power data is negative, the exciting current value of the corresponding small single-phase generator set is increased.
From the above description, the exciting current value of the small-sized single-phase generator set is adjusted according to the magnitude relation between the reactive power data and the idle load, so that the dynamic self-adaptive adjustment is realized, and the effective utilization rate of the small-sized single-phase generator set is maximized.
Further, according to the active power and the frequency data, the corresponding engine output power is adjusted, specifically:
and judging whether the difference between the output frequency of each small single-phase generator in full load and the output frequency in no load is out of a preset threshold range, and if so, adjusting the corresponding engine output power according to the active power and the frequency data. The preset threshold range is 3-7%. For example, the idle frequency is about 5% higher than the rated frequency, the full load is about 5% lower than the idle frequency to reach the rated frequency, the middle is also in a proportional relation, if the frequency is fixed, the power proportion is small, the engine output is increased by the stepping motor, otherwise, the engine output is reduced.
Further, whether a protection mechanism of the small single-phase generator set is triggered is judged according to the active power data, and specifically, the protection mechanism is as follows:
and when the active power data is negative and the absolute value of the active power data is greater than 10% of the total power, controlling the corresponding small-sized single-phase generator set to be disconnected and in parallel with other small-sized single-phase generator sets.
As can be seen from the above description, once the active power data is a negative value, the reverse power state is shown, and when the absolute value of the active power data is greater than 10% of the total power, the reverse power protection mechanism is triggered, that is, the parallel operation state of actively controlling the corresponding small-sized single-phase generator set to disconnect from other small-sized single-phase generator sets is ensured not to affect the operation efficiency of other small-sized single-phase generator sets.
Further, the distortion rate of the output waveform of the small single-phase generator set is less than 10%. The output power of the small single-phase generator set is smaller than 10KW.
As can be seen from the above description, the waveform distortion rate (THD) can reflect the distortion degree of a signal waveform relative to a sinusoidal waveform, and the small single-phase generator with the distortion rate of the output waveform less than 10% is adopted, which has the characteristic of low distortion degree, and is beneficial to accurately controlling the excitation current value and accurately judging whether to trigger the protection mechanism of the small single-phase generator set, so as to improve the operation quality of the generator.
Referring to fig. 1-6, a first embodiment of the present invention is as follows:
the invention provides a parallel operation control method of a small single-phase generator set, which comprises the following steps:
acquiring single-phase current input and single-phase voltage input of each small-sized single-phase generator set in a parallel operation state respectively at the same time, and analyzing to obtain corresponding active power data, reactive power data and frequency data; wherein the distortion rate of the output waveform of the small single-phase generator set is less than 10%. The output power of the small single-phase generator set is smaller than 10KW. The waveform distortion rate (THD) can reflect the distortion degree of a signal waveform relative to a sine waveform, and the small single-phase generator set with the distortion rate smaller than 10% of the output waveform is adopted, so that the small single-phase generator set has the characteristic of low distortion degree, is favorable for accurately controlling the excitation current value and accurately judging whether to trigger a protection mechanism of the small single-phase generator set, and improves the operation quality of the generator.
Adjusting the exciting current value of the corresponding small single-phase generator set according to the reactive power data; the method comprises the following steps:
when the reactive power data is positive, the exciting current value of the corresponding small single-phase generator set is reduced; when the reactive power data is negative, the exciting current value of the corresponding small single-phase generator set is increased. And adjusting the exciting current value of the small single-phase generator set according to the magnitude relation between the reactive power data and the preset threshold value, and realizing dynamic self-adaptive adjustment, so that the effective utilization rate of the small single-phase generator set reaches the maximum.
And judging whether to trigger an inverse power protection mechanism of the small single-phase generator set according to the active power data. The method comprises the following steps:
and when the active power data is negative and the absolute value of the active power data is greater than 10% of the total power, controlling the corresponding small-sized single-phase generator set to be disconnected and in parallel with other small-sized single-phase generator sets. And once the active power data is a negative value, the state is shown to be in an inverse power state, and when the absolute value of the active power data is more than 10% of the total power, an inverse power protection mechanism is triggered, namely, the parallel operation state of the corresponding small single-phase generator set and other small single-phase generator sets is actively controlled to be disconnected, so that the operation efficiency of the other small single-phase generator sets is not influenced.
Adjusting the corresponding engine output power according to the active power and the frequency data; the method comprises the following steps:
and judging whether the difference between the output frequency of each small single-phase generator in full load and the output frequency in no load is out of a preset threshold range, and if so, adjusting the corresponding engine output power according to the active power and the frequency data. The preset threshold range is 3-7%.
Referring to fig. 2-6, a small single-phase generator set parallel operation control circuit correspondingly designed according to the small single-phase generator set parallel operation control method includes a small single-phase generator set and a control module electrically connected with the small single-phase generator set, wherein the control module includes an input end, a first rectifier bridge, a second rectifier bridge, a voltage stabilizing unit, a measuring unit, a measurement and control unit, a first operational amplifier unit, a second operational amplifier unit, a switch unit, an output end and a stepping motor control end;
the first rectifier bridge is electrically connected with the switch unit;
the input end is electrically connected with a second rectifier bridge, the second rectifier bridge is respectively electrically connected with the voltage stabilizing unit, the measuring unit and the first operational amplifier unit, and the measuring unit is electrically connected with the measurement and control unit; the measurement and control unit is electrically connected with the second operational amplifier unit, the stepping motor control end and the parallel operation control end respectively, the second operational amplifier unit is electrically connected with the first operational amplifier unit, the first operational amplifier unit is electrically connected with the switch unit, and the switch unit is electrically connected with the output end.
Wherein, the first rectifying bridge DB1 and the second rectifying bridge DB2 are respectively composed of four diodes.
The voltage stabilizing unit comprises a ninth diode D9, a sixth capacitor C6, a seventh capacitor C7, an eighth capacitor C8, a second voltage stabilizing chip U2 and a third voltage stabilizing chip U3;
the positive electrode of the ninth diode D9 is electrically connected with the second rectifier bridge DB2, and the negative electrode of the ninth diode D9 is electrically connected with a 24V voltage source, one end of a sixth capacitor C6 and the input end of the second voltage stabilizing chip U2; the output end of the second voltage stabilizing chip U2 is electrically connected with the input end of the third voltage stabilizing chip U3 and one end of the seventh capacitor C7 respectively, and the output end of the third voltage stabilizing chip is electrically connected with one end of the eighth capacitor; the other end of the sixth capacitor, the grounding end of the second voltage stabilizing chip, the other end of the seventh capacitor, the grounding end of the third voltage stabilizing chip and the other end of the eighth capacitor are all electrically connected with the grounding end. The output end of the second voltage stabilizing chip outputs 12V voltage, and the output end of the third voltage stabilizing chip outputs 3V3 voltage.
The measuring unit comprises a twenty-sixth resistor R26, a voltage transformer T1, a twenty-seventh resistor R27, a twenty-eighth resistor R28, a twenty-ninth resistor R29, a current transformer CT, a forty-fourth resistor R0 and a thirty-fourth resistor R30;
the second rectifier bridge DB2 is electrically connected with one end of the voltage transformer T1 through a twenty-sixth resistor R26, the twenty-seventh resistor R27 and the twenty-eighth resistor R28 are connected in parallel and then are connected with a twenty-ninth resistor R29 in series, and two ends after the series connection are respectively electrically connected with two sides of the other end of the voltage transformer T1; the two sides of the other end of the voltage transformer T1 are respectively provided with positions with the numbers of IN_1 and IN_2 IN the figure 2 and are used for being connected with pins IN a chip with the number of U10 IN the measurement and control unit to collect voltage data;
the current transformer CT, the forty-fourth resistor R0 and the thirty-fourth resistor R30 are connected in parallel, and two ends of the parallel connected current transformer CT, the forty-fourth resistor R0 and the thirty-fourth resistor R30 are electrically connected with the measurement and control unit. Specifically, the positions labeled in_3 and in_4 IN fig. 2 are connected with pins IN a unit labeled U10 IN the measurement and control unit, so as to collect current data.
The parallel operation control circuit of the small single-phase generator further comprises a thirty-first resistor R31 and a ninth triode Q9; one end of the thirty-first resistor R31 is connected with a pin in a unit with a reference number of U10, the other end of the thirty-first resistor R31 is electrically connected with a ninth triode Q9, and the ninth triode Q9 is used for controlling the conduction state of a main relay of the small-sized single-phase generator so as to control the parallel operation state.
The measurement and control unit is a unit with a reference number of U10, and includes a fourth chip U4, a fifth chip U5, a first pin J1, a second pin J2, a thirty-second resistor R32, a thirty-third resistor R33, a thirty-fourth resistor R34, a thirty-fifth resistor R35, a thirty-sixth resistor R36, a thirty-seventh resistor R37, a thirty-eighth resistor R38, a thirty-ninth resistor R39, a fortieth resistor R40, a fortieth resistor R41, a fortieth resistor R42, a fortieth third resistor R43, a fortieth capacitor C10, an eleventh capacitor C11, a twelfth capacitor C12, a thirteenth capacitor C13, a fourteenth capacitor C14, a fifteenth capacitor C15, a sixteenth capacitor C16, a seventeenth capacitor C17, an eighteenth capacitor C18, a nineteenth capacitor C19, a twentieth capacitor C20, a twenty-first capacitor C21, a twenty-second capacitor C22, and a crystal oscillator Y1;
the first pin of the fourth chip U4 is electrically connected to one end of the forty-first resistor R40, one end of the forty-first resistor R41, and one end of the forty-second resistor R42, respectively; the other end of the forty resistor R40 is electrically connected with one end of a seventeenth capacitor C17 and a fifth pin of a fourth chip U4 respectively, the other end of the forty-first resistor R41 is electrically connected with one end of an eighteenth capacitor C18 and a second pin of the fourth chip U4 respectively, the other end of the seventeenth capacitor C17 and the other end of the eighteenth capacitor C18 are both electrically connected with a grounding terminal, and the other end of the forty-second resistor R42 is electrically connected with a fourth pin of the fourth chip U4; the third pin of the fourth chip is electrically connected with the grounding end through a twenty-first capacitor C21;
the sixth pin of the fourth chip is electrically connected with one end of the tenth capacitor C10, one end of the thirty-second resistor R32 and the fourth pin in_1 of the first pin J1, the seventh pin of the fourth chip is electrically connected with one end of the eleventh capacitor C11, one end of the thirty-third resistor R33 and the third pin in_2 of the first pin J1, and the thirteenth pin of the fourth chip is electrically connected with the other end of the tenth capacitor C10, the other end of the thirty-second resistor R32, the other end of the eleventh capacitor C11 and the other end of the thirty-third resistor R33;
the tenth pin of the fourth chip is electrically connected with one end of a thirty-fourth resistor R34 and one end of a twelfth capacitor C12 respectively, the other end of the thirty-fourth resistor R34 is electrically connected with the second pin in_3 of the first pin J1 and one end of a thirty-fifth resistor R35 respectively, and the other end of the twelfth capacitor C12 and the other end of the thirty-fifth resistor R35 are electrically connected with the thirteenth pin of the fourth chip after being connected;
the eleventh pin of the fourth chip is electrically connected with one end of a thirty-seventh resistor R37 and one end of a thirteenth capacitor C13, the other end of the thirty-seventh resistor R37 is electrically connected with the first pin in_4 of the first pin row and one end of a thirty-sixth resistor R36, and the other end of the thirteenth capacitor C13 and the other end of the thirty-sixth resistor R36 are electrically connected with the thirteenth pin of the fourth chip after being connected;
the fifth pin SX of the first row of pins is electrically connected with the fifth chip U5 through a thirty-ninth resistor R39;
a twelfth pin of the fourth chip is grounded through a twenty-second capacitor C22;
the eighteenth pin SCS, the nineteenth pin SD1, the twentieth pin SD0 and the twenty first pin CLK of the fourth chip are respectively and electrically connected with the fifth chip;
the twenty-second pin of the fourth chip is electrically connected with one end of the crystal oscillator tube Y1, one end of the forty-third resistor R43 and one end of the twentieth capacitor C20 respectively; the twenty-third pin of the fourth chip is electrically connected with the other end of the crystal oscillator tube Y1, the other end of the forty-third resistor R43 and one end of the nineteenth capacitor C19 respectively; the other end of the twentieth capacitor C20 is electrically connected with the ground terminal after being connected with the other end of the nineteenth capacitor C19;
the RST pin of the fifth chip is electrically connected with one end of a thirty-eighth resistor R38 and one end of a fifteenth capacitor C15 respectively, the other end of the thirty-eighth resistor R38 is electrically connected with a power supply end, and the other end of the fifteenth capacitor C15 is electrically connected with a grounding end;
the VCAP pin of the fifth chip is grounded through a sixteenth capacitor C16;
one end of the fourteenth capacitor C14 is electrically connected with the power supply end, and the other end of the fourteenth capacitor C is electrically connected with the grounding end;
and the pins BJ 1-BJ 4 and JDQ 0-JDQ 4 of the fifth chip are respectively and correspondingly electrically connected with the second row.
The second operational amplifier unit comprises an eighteenth resistor R18, a nineteenth resistor R19, a twentieth resistor R20, a twenty-first resistor R21, a twenty-second resistor R22, a twenty-third resistor R23, a twenty-fourth resistor R24, a twenty-fifth resistor R25, a ninth capacitor C9 and a second operational amplifier U1B;
one end of the eighteenth resistor R18 and one end of the twentieth resistor R20 are respectively and electrically connected with a 3V3 power supply, the other end of the twentieth resistor R20 is electrically connected with a JDQ3 pin of a fifth chip and one end of the twenty-first resistor R21, the other end of the twenty-first resistor R21 is respectively and electrically connected with one end of a ninth capacitor C9 and one end of a twenty-second resistor R22, the other end of the ninth capacitor C9 is grounded, the other end of the twenty-second resistor R22 is respectively and electrically connected with the other end of the eighteenth resistor R18, one end of a nineteenth resistor R19 and one end of a twenty-third resistor R23, and the other end of the nineteenth resistor R19 is grounded with a fourth pin of the second operational amplifier U1B; the other end of the twenty-third resistor R23 is electrically connected with a positive input end (fifth pin) of the second operational amplifier U1B, a negative input end (sixth pin) of the second operational amplifier U1B is electrically connected with one end of a twenty-fourth resistor R24 and one end of a twenty-fifth resistor R25 respectively, the other end of the twenty-fifth resistor R25 is grounded, an eighth pin of the second operational amplifier U1B is connected with a 12V power supply, and the other end of the twenty-fourth resistor R24 is electrically connected with an output end (eighth pin) of the second operational amplifier U1B;
the output end (eighth pin) of the second operational amplifier U1B is electrically connected with the first operational amplifier unit;
in the scheme, the measuring IC adopts an integrated chip with the model of ATT7053 AU.
The first operational amplifier unit includes a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a fourteenth resistor R14, a seventeenth resistor R17, an adjustable resistor VR1, a third capacitor C3, a fourth capacitor C4, a fifth capacitor C5, a twelfth diode D10, and a first operational amplifier U1A;
the second rectifier bridge DB2 is electrically connected to one end of a seventh resistor R7 and one end of an eighth resistor R8, the other end of the seventh resistor R7 is electrically connected to one end of a ninth resistor R9, one end of a tenth resistor R10 and one end of a twelfth resistor R12, the other end of the eighth resistor R8 is electrically connected to the other end of the ninth resistor R9 and one end of an eleventh resistor R11, and the other end of the eleventh resistor R11 is grounded through a third capacitor C3; the other end of the twelfth resistor R12 is grounded after sequentially passing through a tenth diode D10 and an adjustable resistor VR1 which are connected in series; the other end of the tenth resistor R10 is electrically connected with the positive input end (third pin) of the first operational amplifier U1A;
the reverse input end (second pin) of the first operational amplifier U1A is electrically connected with one end of a fourth capacitor C4 and one end of a seventeenth resistor R17 respectively, the other end of the seventeenth resistor R17 is electrically connected with one end of a fifth capacitor C5 and the output end of the second operational amplifier U1B respectively, and the other end of the fifth capacitor C5 is grounded; the other end of the fourth capacitor C4 is electrically connected with the output end (first pin) of the first operational amplifier U1A through a fourteenth resistor R14, the eighth pin of the first operational amplifier U1A is connected with a 12V power supply, and the fourth pin of the first operational amplifier U1A is grounded;
the switching unit comprises a thirteenth resistor R13, a sixth resistor R6, a fifteenth resistor R15, a sixteenth resistor R16, a zener diode Z1, a sixth diode D6, a seventh diode D7, an eighth diode D8, a fifth triode Q5, a sixth triode Q6, a seventh triode Q7, an eighth triode Q8 and a second capacitor C2;
one end of the thirteenth resistor R13 is electrically connected with the output end (the first pin) of the first operational amplifier U1A, the other end of the thirteenth resistor R13 is electrically connected with the negative electrode of the zener diode Z1, the positive electrode of the zener diode Z1 is electrically connected with one end of the sixth resistor R6, one end of the fifteenth resistor R15 and the base electrode of the fifth triode Q5, the other end of the fifteenth resistor R15 is electrically connected with the ground end, the emitter of the fifth triode Q5 is electrically connected with the ground end, and the other end of the sixth resistor R6 is electrically connected with one end of the second capacitor C2;
the collector of the fifth triode Q5 is electrically connected with the base electrode of the sixth triode Q6, and the other end of the second capacitor C2, the collector of the sixth triode Q6, the collector of the seventh triode Q7, the anode of the sixth diode D6 and the cathode of the seventh diode D7 are electrically connected with each other;
the emitter of the sixth triode Q6 is respectively and electrically connected with the cathode of the eighth diode D8 and the base of the seventh triode Q7, the anode of the eighth diode D8 is respectively and electrically connected with the emitter of the seventh triode Q7, the base of the eighth triode Q8 and one end of the sixteenth resistor R16,
the negative electrode of the sixth diode D6 is electrically connected to the collector of the eighth triode Q8, and the other end of the sixteenth resistor R16, the emitter of the eighth triode Q8, and the positive electrode of the seventh diode D7 are all electrically connected to the ground terminal.
The device further comprises a first capacitor C1, a fifth resistor R5 and a fifth diode D5;
the first capacitor C1 is connected in parallel with the first rectifier bridge DB1, one end of the parallel connection is grounded, the other end of the parallel connection is electrically connected with one end of the fifth resistor R5 and the negative electrode of the fifth diode D5, the other end of the fifth resistor R5 is electrically connected with the base electrode of the sixth triode Q6, the positive electrode of the fifth diode D5 is electrically connected with the other end of the second capacitor C2, and the two ends of the fifth diode D5 are used for connecting the exciting winding in parallel; the other end of the second capacitor C2 is used as the output end;
the control end of the stepping motor comprises a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a first triode Q1, a second triode Q2, a third triode Q3 and a fourth triode Q4;
one end of the first resistor R1 is electrically connected with a BJ1 pin of the fifth chip, the other end of the first resistor R1 is electrically connected with a base electrode of the first triode Q1, a collector electrode of the first triode Q1 is electrically connected with an anode of the first diode D1, and a cathode of the first diode D1 is electrically connected with a 12V power supply;
one end of the second resistor R2 is electrically connected with a BJ2 pin of the fifth chip, the other end of the second resistor R2 is electrically connected with a base electrode of a second triode Q2, a collector electrode of the second triode Q2 is electrically connected with an anode of a second diode D2, and a cathode of the second diode D2 is electrically connected with a 12V power supply;
one end of the third resistor R3 is electrically connected with a BJ3 pin of the fifth chip, the other end of the third resistor R3 is electrically connected with a base electrode of a third triode Q3, a collector electrode of the third triode Q3 is electrically connected with an anode of a third diode D3, and a cathode of the third diode D3 is electrically connected with a 12V power supply;
one end of the fourth resistor R4 is electrically connected with a BJ4 pin of the fifth chip, the other end of the fourth resistor R4 is electrically connected with a base electrode of a fourth triode Q4, a collector electrode of the fourth triode Q4 is electrically connected with an anode of a fourth diode D4, and a cathode of the fourth diode D4 is electrically connected with a 12V power supply;
the stepping motor comprises four windings, namely a first winding, a second winding, a third winding and a fourth winding; two ends of the first winding are respectively connected with a collector electrode (PIN 1 PIN) of the first triode Q1 and a 12V power supply (PIN 5 PIN); two ends of the second winding are respectively connected with a collector electrode (PIN 2 PIN) of the second triode Q2 and a 12V power supply (PIN 5 PIN); two ends of the third winding are respectively connected with a collector electrode (PIN 3 PIN) of the third triode Q3 and a 12V power supply (PIN 5 PIN); both ends of the fourth winding are respectively connected with a collector (PIN 4 PIN) and a 12V power supply (PIN 5 PIN) of the fourth triode Q4. According to the connection relation, the running state of the stepping motor and related parameters can be controlled.
The parallel operation control circuit of the small single-phase generator set has the following working principle:
the measuring winding (white and green wires, namely PIN6 and PIN7 PINs in fig. 2) of the generator is rectified by a rectifier bridge DB2, isolated by a diode D9, filtered by a capacitor C6 to generate a +24V power supply, regulated by a regulating circuit U2, filtered by a capacitor C7 to generate a 12V power supply, and filtered by a regulating circuit U3 and a capacitor C8 to generate a +3.3V power supply. Meanwhile, the measuring winding is limited by a resistor R26 and then is converted by a current-type voltage transformer T1 to generate measuring voltages on resistors R27, R28 and R29, and the measuring voltages are sent to voltage input ends IN1 and IN2 of a measuring control circuit U10.
After the current of the main loop of the generator is shunted by the current transformer CT variable current external resistor R0, a main loop current measurement signal (different resistance values of the external resistor R0 so as to adapt to different capacities or units with different performances) is generated on the resistor R30 and is sent to the current input ends IN3 and IN4 of the U10.
The measurement control circuit U10 is arranged on the circuit board G133-3, the inside of the measurement control circuit is composed of a measurement circuit formed by a measurement module U4 and auxiliary elements, a control circuit formed by a singlechip U5 and auxiliary elements, and the 7-hole pin J1 is used as an input end and the 9-hole pin J2 is used as an output end. GND, VCC, SX of J1 are respectively a grounding end, a power supply and a program programming end, IN 1-IN 4 are respectively connected with a current voltage signal end of a measuring module U4, U4 measures electric parameters such as voltage, current, active power, reactive power, power factors, frequency and the like of a generator, and a singlechip U5 IN U10 reads the measured electric parameters of U4 and works according to an input internal program.
According to reactive power, the JDQ3 output end of U5 outputs square waves with different duty ratios through J2, and is connected with a pull-up resistor R20 filter capacitor resistor C9 and R21 for filtering and converting into direct current voltage, the direct current voltage is divided by R22.R18.R19 and amplified by U1B, and then the voltage is outputted by U1B7 as a given voltage of the AVR. The voltage is connected to the 2 pin of U1A through R17, the generator measurement winding (white and green line) is rectified through rectifier bridge DB2, then regulated through resistors R7, R8, R9, R11, R12, capacitor C3 and diode D10, the voltage is regulated through resistor R10, the signal generated by the 1 pin of U1A after the comparison and amplification of the 3 pin and the 2 pin of U1A is connected to the given voltage of U1A, the on-off of triode Q5 is controlled through resistor R13 voltage regulator Z1, and the exciting voltage and current of the generator are regulated through the on-off of Q8 after the three-stage Darlington circuit consisting of triodes Q6, Q7 and Q8 is amplified.
When the unit power is 0, the given voltage output by the U1B7 pin after the JDQ3 output square wave of the U5 is subjected to filtering voltage division and then amplified by the U1B is about 6V8 in average value, when the inductive reactive power is increased, the given voltage is reduced in proportion (the proportion is about 50% of the inductive reactive power and the given voltage is reduced by about 6%) and when excitation is underexcited (insufficient), the given voltage is increased in proportion, the power is reversed, and the given voltage is increased. The droop characteristic of the reactive power is utilized to achieve the automatic balance of the reactive power during parallel operation, and of course, the active power can be moderately reduced by a given voltage when the power is increased, and the reduction ratio is smaller than the reactive ratio.
According to active power and frequency data, BJ1, BJ2, BJ3 and BJ4 output ends of U5 control on-off of triodes Q1, Q2, Q3 and Q4 through J2 output and current limiting resistors R1, R2, R3 and R4, and PIN5 output ends of PIN1, PIN2, PIN3, PIN4 and +12V end control forward and reverse rotation of a stepping motor, diodes D1, D2, D3 and D4 are freewheeling diodes of coils of the stepping motor, the forward and reverse rotation of the stepping motor changes tension of a tension spring, and an engine throttle is pulled to change engine speed and output.
When the engine leaves the factory, the idle frequency is about 5% higher than the rated frequency, namely 52.5HZ (63 HZ) is fully loaded, and the idle frequency is about 5% reduced on the basis, namely the middle of the rated frequency 50HZ (60 HZ) is basically in a linear relation, and the idle frequencies of the two engines are basically adjusted to be consistent in parallel operation. If the full load frequency of the two machines is reduced uniformly, the load proportion of the two machines is uniform during full load, so that the two machines can operate well, the maximum output of the two machines can be achieved, if the frequency is reduced to be inconsistent during full load, the load proportion of the parallel machine after the two machines with large frequency is smaller than that of the other machine, and the electric large output of the two machines cannot be achieved.
In order to achieve the maximum output of the two machines, the full-load frequency of the two machines must be controlled to be consistent, and the frequencies of the two machines are identical in parallel operation. As long as it is in terms of frequency and power. The stepping motor is controlled according to the intermediate proportion that the power is 0 at 105 percent of rated frequency, namely 52.5HZ (63 HZ), and 100 percent of rated frequency, namely 50HZ (60 HZ), and if the power proportion is small, the output of the motive power is increased through the forward rotation of the stepping motor, otherwise, the output of the engine is reduced.
In parallel operation, if the engine does not have fuel oil or other faults and does not do work, the generator becomes a motor to drag the engine to operate, at the moment, the output power of the generator becomes input power, namely reverse power, when the reverse power reaches a certain value, U5 outputs 0 level through the JDQ4 end of the output end J2 to enable Q9 to be not conducted to disconnect the main relay, so that the unit is disconnected from other power sources, and the parallel operation is stopped.
Experimental data for this protocol are as follows:
TABLE 1
TABLE 2
TABLE 3 Table 3
TABLE 4 Table 4
The above tables 1-4 are related experimental data obtained through testing, and particularly, as can be seen from table 4, when no-load of the machine # 1 and the machine # 2 are inconsistent, the speed regulating device is added, namely the parallel operation control method of the small single-phase generator set and the correspondingly developed circuit structure are adopted, so that the full-load frequency drop of the two machines is controlled to be consistent, the frequency is the same in parallel operation, and finally, the maximum output of the two machines is achieved.
In summary, the parallel operation control method of the small single-phase generator sets provided by the invention adopts an independent control mode of each small single-phase generator set, and obtains the single-phase current input and the single-phase voltage input of each small single-phase generator set in a parallel operation state at the same time, so as to analyze and obtain corresponding active power data, reactive power data and frequency data; the active power data, the reactive power data and the frequency data are further analyzed to adjust the exciting current value and the engine output power of the corresponding small single-phase generator set and serve as judgment standards for triggering a protection mechanism of the small single-phase generator set, intelligent control of the generator is achieved, parallel operation of the small single-phase generator set is guaranteed, and the effective utilization rate of the generator is improved to the greatest extent.
The foregoing description is only illustrative of the present invention and is not intended to limit the scope of the invention, and all equivalent changes made by the specification and drawings of the present invention, or direct or indirect application in the relevant art, are included in the scope of the present invention.
Claims (5)
1. The parallel operation control method of the small single-phase generator set is characterized by comprising the following steps of:
acquiring single-phase current input and single-phase voltage input of each small-sized single-phase generator set in a parallel operation state respectively at the same time, and analyzing to obtain corresponding active power data, reactive power data and frequency data;
adjusting the exciting current value of the corresponding small single-phase generator set according to the reactive power data; adjusting the corresponding engine output power according to the active power and the frequency data; judging whether to trigger an inverse power protection mechanism of the small single-phase generator set according to the active power data;
the corresponding engine output power is adjusted according to the active power and the frequency data, specifically:
judging whether the difference between the output frequency of each small single-phase generator in full load and the output frequency in no load is out of a preset threshold range, if so, adjusting the corresponding engine output power according to the active power and the frequency data;
if the frequency is fixed, the power proportion is small, the engine output is increased through the stepping motor, otherwise, the engine output is reduced;
the preset threshold range is 3-7%.
2. The parallel operation control method of the small-sized single-phase generator set according to claim 1, wherein the excitation current value of the corresponding small-sized single-phase generator set is adjusted according to reactive power data, specifically:
when the reactive power data is positive, the exciting current value of the corresponding small single-phase generator set is reduced; when the reactive power data is negative, the exciting current value of the corresponding small single-phase generator set is increased.
3. The parallel operation control method of the small single-phase generator set according to claim 1, wherein the method is characterized in that whether a protection mechanism of the small single-phase generator set is triggered is judged according to active power data, and specifically comprises the following steps:
and when the active power data is negative and the absolute value of the active power data is greater than 10% of the total power, controlling the corresponding small-sized single-phase generator set to be disconnected and in parallel with other small-sized single-phase generator sets.
4. The parallel operation control method of the small single-phase generator set according to claim 1, wherein the distortion rate of the output waveform of the small single-phase generator set is less than 10%.
5. The parallel operation control method of a small single-phase generator set according to claim 1, wherein the output power of the small single-phase generator set is less than 10KW.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102307036A (en) * | 2011-03-15 | 2012-01-04 | 隆鑫通用动力股份有限公司 | Control method and device for parallel running of internal combustion engine-driven generating sets |
| CN102307037A (en) * | 2011-03-15 | 2012-01-04 | 隆鑫通用动力股份有限公司 | Control method and device for parallel running of internal combustion engine-driven generating sets |
| CN102971927A (en) * | 2010-09-01 | 2013-03-13 | 科勒公司 | System and method for paralleling electrical power generators |
| CN105071432A (en) * | 2015-07-31 | 2015-11-18 | 太原理工大学 | Diesel generator parallel control apparatus |
| CN105634021A (en) * | 2016-01-29 | 2016-06-01 | 重庆力华自动化技术有限责任公司 | Power balance control method for internal combustion engine driven generator set parallel operation |
| CN106026196A (en) * | 2016-07-28 | 2016-10-12 | 西安交通大学 | Multi-virtual synchronous generator parallel network control method based on inverter |
| CN107634545A (en) * | 2017-09-21 | 2018-01-26 | 北京机械设备研究所 | A kind of alternating current generator sets in parallel operation power distribution method of dissymmetrical structure |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7319307B2 (en) * | 2005-12-16 | 2008-01-15 | General Electric Company | Power balancing of multiple synchronized generators |
-
2019
- 2019-04-12 CN CN201910292040.0A patent/CN109921468B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102971927A (en) * | 2010-09-01 | 2013-03-13 | 科勒公司 | System and method for paralleling electrical power generators |
| CN102307036A (en) * | 2011-03-15 | 2012-01-04 | 隆鑫通用动力股份有限公司 | Control method and device for parallel running of internal combustion engine-driven generating sets |
| CN102307037A (en) * | 2011-03-15 | 2012-01-04 | 隆鑫通用动力股份有限公司 | Control method and device for parallel running of internal combustion engine-driven generating sets |
| CN105071432A (en) * | 2015-07-31 | 2015-11-18 | 太原理工大学 | Diesel generator parallel control apparatus |
| CN105634021A (en) * | 2016-01-29 | 2016-06-01 | 重庆力华自动化技术有限责任公司 | Power balance control method for internal combustion engine driven generator set parallel operation |
| CN106026196A (en) * | 2016-07-28 | 2016-10-12 | 西安交通大学 | Multi-virtual synchronous generator parallel network control method based on inverter |
| CN107634545A (en) * | 2017-09-21 | 2018-01-26 | 北京机械设备研究所 | A kind of alternating current generator sets in parallel operation power distribution method of dissymmetrical structure |
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